Abstract
We discuss the Cottingham formula and evaluate the proton–neutron electromagnetic mass difference exploiting the state-of-the-art phenomenological input. We decompose individual contributions to the mass splitting into Born, inelastic and subtraction terms. We evaluate the subtraction-function contribution connecting the input based on experimental data with the operator product expansion matched to QCD which allows us to avoid model dependence and to reduce errors of this contribution. We evaluate inelastic and Born terms accounting for modern low-\(Q^2\) data.
Similar content being viewed by others
Notes
Without inputs from Ref. [32], the subtraction term contributes \(\delta M^{\mathrm {subt}}_{p-n} = 0.54 \pm 0.46~\mathrm {MeV}\).
The proton and neutron mass corrections based on the state-of-the-art fits from Ref. [46] are in agreement with our results and have smaller uncertainties.
A naive assignment of 3–5% error to nucleon structure functions gives an uncertainty estimate comparable to the inelastic contribution. A proper error estimate calls for reanalysis of nucleon structure functions taking correlations into account.
References
M. Tanabashi et al., Phys. Rev. D. 98(3), 030001 (2018)
W.N. Cottingham, Ann. Phys. 25, 424 (1963)
A. Zee, Phys. Rep. 3, 127 (1972)
J. Gasser, H. Leutwyler, Nucl. Phys. B 94, 269 (1975)
J. C. Collins, Nucl. Phys. B 149, 90 (1979) Erratum: [Nucl. Phys. B 153, 546 (1979)] Erratum: [Nucl. Phys. B 915, 392 (2017)]
A. Walker-Loud, C.E. Carlson, G.A. Miller, Phys. Rev. Lett. 108, 232301 (2012)
J. Gasser, M. Hoferichter, H. Leutwyler, A. Rusetsky, Eur. Phys. J. C 75(8), 375 (2015)
J. Gasser, H. Leutwyler, A. Rusetsky,. arXiv:2003.13612 [hep-ph]
A.W. Thomas, X.G. Wang, R.D. Young, Phys. Rev. C 91(1), 015209 (2015)
F.B. Erben, P.E. Shanahan, A.W. Thomas, R.D. Young, Phys. Rev. C 90(6), 065205 (2014)
M.G. Endres, A. Shindler, B.C. Tiburzi, A. Walker-Loud, Phys. Rev. Lett. 117(7), 072002 (2016)
S.R. Beane, K. Orginos, M.J. Savage, Nucl. Phys. B 768, 38 (2007)
G.M. de Divitiis et al., JHEP 1204, 124 (2012)
N.F. Nasrallah, Phys. Rev. C 87(5), 055203 (2013)
N.F. Nasrallah, Addendum: [Phys. Rev. C 87, 059903 (2013)]
N.F. Nasrallah, [Addendum: Phys. Rev. C 87(6), 069903 (2013)]
R. Horsley et al., [QCDSF and UKQCD Collaborations]. Phys. Rev. D 86, 114511 (2012)
P.E. Shanahan, A.W. Thomas, R.D. Young, Phys. Lett. B 718, 1148 (2013)
T. Blum, R. Zhou, T. Doi, M. Hayakawa, T. Izubuchi, S. Uno, N. Yamada, Phys. Rev. D 82, 094508 (2010)
S. Borsanyi et al. [Budapest-Marseille-Wuppertal Collaboration], Phys. Rev. Lett. 111(25), 252001 (2013)
S. Borsanyi et al., Science 347, 1452 (2015)
R. Horsley et al., J. Phys. G 43(10), 10LT02 (2016)
M.C. Birse, J.A. McGovern, Eur. Phys. J. A 48, 120 (2012)
A. Sibirtsev, P.G. Blunden, W. Melnitchouk, A.W. Thomas, Phys. Rev. D 82, 013011 (2010)
A. Sibirtsev, P.G. Blunden, Phys. Rev. C 88(6), 065202 (2013)
O. Tomalak, M. Vanderhaeghen, Eur. Phys. J. C 76(3), 125 (2016)
O. Tomalak, Eur. Phys. J. A 55(5), 64 (2019). https://doi.org/10.1140/epja/i2019-12743-1
H. Pilkuhn, W. Schmidt, A.D. Martin, C. Michael, F. Steiner, B.R. Martin, M.M. Nagels, J.J. de Swart, Nucl. Phys. B 65, 460 (1973)
A. Donnachie, P.V. Landshoff, Phys. Lett. B 595, 393 (2004)
P.E. Bosted, M.E. Christy, Phys. Rev. C 77, 065206 (2008)
M.E. Christy, P.E. Bosted, Phys. Rev. C 81, 055213 (2010)
R.J. Hill, G. Paz, Phys. Rev. D 95(9), 094017 (2017)
H.R. Weller, M.W. Ahmed, H. Gao, W. Tornow, Y.K. Wu, M. Gai, R. Miskimen, Prog. Part. Nucl. Phys. 62, 257 (2009)
V. Sokhoyan et al., Eur. Phys. J. A 53(1), 14 (2017)
E.J. Downie, et al., Proposal for MAMI-A2/04-16 (2016)
J.R.M. Annand, et al., Proposal for MAMI-A2-01/13: Compton Scattering on the He Isotopes with an Active Target (2013)
J.M. Alarcon, V. Lensky, V. Pascalutsa, Eur. Phys. J. C 74(4), 2852 (2014)
V. Lensky, F. Hagelstein, V. Pascalutsa, M. Vanderhaeghen, Phys. Rev. D 97(7), 074012 (2018)
J.C. Bernauer et al., [A1 Collaboration], Phys. Rev. Lett. 105, 242001 (2010)
J.C. Bernauer et al., Phys. Rev. C 90(1), 015206 (2014)
G. Kubon et al., Phys. Lett. B 524, 26 (2002)
G. Warren et al., Phys. Rev. Lett. 92, 042301 (2004)
J.J. Kelly, Phys. Rev. C 70, 068202 (2004)
V. Punjabi, C.F. Perdrisat, M.K. Jones, E.J. Brash, C.E. Carlson, Eur. Phys. J. A 51, 79 (2015)
Z. Ye, J. Arrington, R.J. Hill, G. Lee, Phys. Lett. B 777, 8 (2018)
K. Borah, R.J. Hill, G. Lee, O. Tomalak, arXiv:2003.13640 [hep-ph]
Acknowledgements
We acknowledge Vadim Lensky and Marc Vanderhaeghen for useful discussion. This work was supported in part by the Deutsche Forschungsgemeinschaft (DFG) through Collaborative Research Center “The Low-Energy Frontier of the Standard Model” (SFB 1044), in part by a NIST precision measurement grant and by the U. S. Department of Energy, Office of Science, Office of High Energy Physics, under Award No. DE-SC0019095, and in part by the Visiting Scholars Award Program of the Universities Research Association.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Tomalak, O. Electromagnetic proton–neutron mass difference. Eur. Phys. J. Plus 135, 411 (2020). https://doi.org/10.1140/epjp/s13360-020-00413-9
Received:
Accepted:
Published:
DOI: https://doi.org/10.1140/epjp/s13360-020-00413-9